The antiepileptic drug (AED) sodium valproate (SVA) is a nonspecific inhibitor of HDAC9 activity7 and has been shown to attenuate atherosclerosis in apolipoprotein E–deficient mice.8 A large Danish study suggested that although epilepsy was associated with an increased risk of incident stroke, the extent of this effect varied with the type of AED that was prescribed. This evidence concerns the gene HDAC9 and Stroke.